- Benign Cartilage Tumors
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- Osteochondroma
- Enchondroma
- Multiple enchondromatosis
- Juxtacortical (periosteal) chondroma
- Chondromyxoid fibroma
- Chondroblastoma
- Synovial chondromatosis
- Malignant cartilage tumors
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- Malignant Chondrosarcoma
- Dedifferentiated chondrosarcoma
- Mesenchymal chondrosarcoma
- Clear cell chondrosarcoma
Cartilage tumors vary in severity from benign enchondroma to low-grade malignant chondrosarcoma to the highest-grade dedifferentiated chondrosarcoma.
Chondrosarcoma is the second most common primary malignant bone tumor,
accounting for 10-20% of all primary bony malignancies
Enchondroma,
which consists of benign endosteal cartilage,
is much more common than chondrosarcoma
Distinguishing benign cartilage tumors from low-grade malignant cartilage tumors poses difficulties
Location - Most cartilage tumors of the hands and feet are benign,
whereas cartilage tumors of the pelvis,
scapula,
and sternum are more likely to be malignant [10]
Size - Most enchondromas are smaller than 3 cm; benign tumors larger than 5 cm are uncommon
Pain - Both benign and malignant cartilage tumors may be associated with pain; however,
a careful history characterizing the pain may help distinguish pain due to arthrosis of an adjacent joint or other causes of limb pain from pain associated with an underlying bone lesion
Radiographic features - Radiographs are crucial in distinguishing chondrosarcomas from enchondromas
Enchondromas :well marginated ,characteristic punctate or flocculent intralesional mineralization pattern that is the hallmark of calcified hyaline cartilage,
expansion of the cortex,
endosteal scalloping with no frank erosions (especially in flat bones)
Chondrosarcomas: extensive endosteal erosion,
especially involving more than one half to two thirds the width of the cortex,
should increase suspicion of malignancy,
whereas frank cortical destruction and soft tissue extension should be considered evidence of malignancy
CT : is particularly useful in evaluating the relation of an endosteal cartilage tumor to the adjacent cortex.
An enchondroma is expected to have an intact rind of cortical bone surrounding it
Magnetic resonance imaging - MRI signal characteristics,
such as increased signal intensity on T2-weighted images,
heterogeneity of the matrix,
and lack of intralesional mineralization,
are suggestive of malignancyVariants of chondrosarcoma:
-Central Versus peripheral
-Primary versus Secondary
Secondary
Twelve per cent of all chondrosarcomas are developed in a pre-existing lesion.
It may be secondary to: a solitary osteochondroma,
osteochondromatosis,
enchondromatosis (Ollier’s disease),
fibrous dysplasia,
Paget’s disease,
irradiated bone or synovial chondromatosis [1].
In osteochondromatosis the risk of sarcomatous transformation is 5–25%,
it is 25–50% in enchondromatosis and nearly 100% in Maffucci’s
Twelve per cent of all chondrosarcomas are developed in a pre-existing lesion.
It may be secondary to: a solitary osteochondroma,
osteochondromatosis,
enchondromatosis (Ollier’s disease),
fibrous dysplasia,
Paget’s disease,
irradiated bone or synovial chondromatosis [1].
In osteochondromatosis the risk of sarcomatous transformation is 5–25%,
it is 25–50% in enchondromatosis and nearly 100% in Maffucci’s
Atypical forms:
Peri osteal chondrosarcoma
-Clear cell chondrosarcoma
-Extra skeletal chondro sarcoma(Myxoid and mesenchymal)
-Dedifferentiated
Clear cell Chondro sarcoma
rare form (2%) of chondrosarcoma,
these lesions are distinguished by their cytology,
epiphyseal location in long bones,
and slow evolution
Age:19-68 years predominantly after epiphyseal fusion
Often mistaken for a chondroblastoma
There is a male predominance and most patients are in their third to fifth decade
It is a Low grade chondrosarcoma variant
The commonest sites are the femur,
humerus and tibia.
This low-grade tumour shows a geographic lytic epiphyseal lesion with extension to the metaphysis.Well defined usually,No soft tissue extension,matrix Mineralization icommon but not always demonstrable.
CT may be useful to depict lobulated margins and calcified matrix
MRI shows well-delineated low signal on T1 weighted images and heterogeneous high signal on T2 images.
DDX: Chondroblastoma,Giant cell tumors due to subarticular location but can be differentiated on its T2 signal as it is very bright on t2 unlike GCT
Extra skeletal chondro sarcoma can be Myxoid or mesenchymal types
Mesenchymal chondro sarcoma can be of both skeletal or extra skeletal involvement
Extra skeletal Myxoid chondrosarcoma:
1-2% of all soft tissue sarcomas
Age:Mean age of 50 years
Location: thigh most common
Slowly growing soft tissue mass with pain and tenderness
Metastatic in 40-45% at the time of presentation.
Site: deep soft tissues,
sub cutis in 25%
CT:
Lobulated soft tissue mass with out calcification or ossification
4-7cm in diameter usually
MR:
Approximately equal to muscle on T1 equal to fat on T2
May mimic a cyst or a Myxoma
Mesenchymal chondro sarcoma
.Skeletal
The tumors are large and destructive lesions,
some have a purely lytic pattern.
Calcified masses can be found.
The lesion appears of low signal intensity on T1 weighted MRI and heterogeneous high signal on T2 images
.Extra skeletal
This entity,
representing 2–3% of all chondro sarcomas,
combines an undifferentiated cell component with well-differentiated cartilaginous areas
50% of mesenchymal chondro sarcomas arise in soft tissues.
Bimodal age distribution
M=F
Common skeletal sites are the femur,
pelvic bones,
ribs and vertebrae.
About one-third of cases involve the extra osseous sites: brain,
meninges,
or soft tissues,peri orbital region ,head and neck : 3rd decade
Tumors of thigh: 5th decade
CT
Metastasize to Lungs and lymph nodes.
Matrix Mineralization in 50% with rings+arcs+flocculent or stippled calcification
Dense mineralization pattern
MRI: Iso intense to muscle on T1 and to fat on T2,matrix signal voids due to calcifications,
homogeneous enhancement.
Histopathology:
Small primitive mesenchymal cellular proliferation with islands of cartilage scattered through out
Haemangio Peri cytoma like Vascular pattern
Dedifferentiated chondro sarcoma
This form represents 10–12% of all chondrosarcomas.
It is characterised by a special histology and very poor prognosis.
T
he biphasic tumour associates a low-grade chondrosarcoma with a non-chodroid high-grade sarcoma Pain and swelling are the usual clinical symptoms as well as pathological fractures The commonest locations are the femur,
the acetabular regions and the proximal humerus.
These metaphyseal or diaphyseal lesions are rapidly destructive.
The osteolytic lesion may predominate,
but usually the lytic area is associated with calcifications resulting in the bimorphic pattern
A huge soft-tissue mass without calcifications,
seen on CT or MRI is also indicative for this diagnosis.
Imaging helps to direct biopsy of the lytic area in order to improve the histological diagnosis.
The treatment involves surgery and adjuvant chemotherapy or radiotherapy.
The prognosis is very poor,
with an overall 5-year survival rate of only 8.5–13%.
The metastases appear in the lungs but also in unusual sites such as the adrenal gland,
brain and liver.